Navigate to this file (your roster URL, and append '/phpinfo.php'), and in the output find 'upload_max_filesize'

The number next to this is the maximum size of uploaded files to your server.

If it is less than the size of your CP.lua, you're screwed. NetherPanel has a feature to split up CP.lua in smaller, valid chunks. I think UU has that too nowadays, but I'm not sure. You could also try contacting your host about it.